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21.
Knowledge and Information Systems - Given sequential news watch logs of users, how can we accurately recommend news articles? Compared to other items (e.g., movies and e-commerce products) for a... 相似文献
22.
Gary Gibson Xia Sheng Dick Henze Si‐Ty Lam Patricia Beck Yoocharn Jeon Zhang‐Lin Zhou Brad Benson Qin Liu Gregg Combs Tim Koch Kent Biggs 《Journal of the Society for Information Display》2012,20(10):552-558
Reflective displays are advantageous in applications requiring low power or daylight readability. However, there are no low‐cost reflective technologies capable of displaying bright colors. By employing photoluminescence to more efficiently use ambient light, we created a prototype display that provides bright, full color in a simple, low‐cost architecture. This prototype includes a novel electrokinetic shutter, a layer that incorporates patterned luminescent red, green, and blue sub‐pixel elements, and a novel optical out‐coupling scheme. The luminescent elements convert otherwise‐wasted portions of the incident spectrum to light in the desired color band, resulting in improved color saturation and lightness. This prototype provides a color gamut that is superior to competing reflective display technologies that utilize color filters in single‐layer side‐by‐side sub‐pixel architectures. The current prototype is capable of switching in <0.5 s; future displays based on an alternative electro‐optic shutter technology should achieve video rate operation. A transflective version of this technology has also been prototyped. The transflective version utilizes its backlight with a power efficiency that is at least three times that of a conventional liquid crystal display. These photoluminescence‐based technologies enable a host of applications ranging from low‐power mobile products and retail pricing signage to daylight readable signage for outdoor advertising segments. 相似文献
23.
An investigation into vehicle rollover prevention by coordinated control of active anti-roll bar and electronic stability program 总被引:1,自引:0,他引:1
Seongjin Yim Kwangki Jeon Kyongsu Yi 《International Journal of Control, Automation and Systems》2012,10(2):275-287
This paper presents a method for designing a controller that uses an active anti-roll bar (AARB) and an electronic stability program (ESP) for rollover prevention. ESP with longitudinal speed control (LSC) can carry out active braking to reduce vehicle speed and lateral acceleration to prevent a rollover. To enhance the rollover prevention capability of the ESP, an AARB is adopted. The controller for the AARB was designed based on linear quadratic (LQ) static output feedback (SOF) control methodology, which attenuates the effect of lateral acceleration on the roll angle and roll rate by control of the suspension stroke and the tire deflection of the vehicle. Although this AARB significantly increases ride comfort and rollover prevention, it has a drawback — the vehicle loses its maneuverability. Therefore, the ESP with LSC is used to overcome this drawback. Simulations showed that the proposed method was effective in preventing a rollover. 相似文献
24.
25.
Jaewan Jeon Sungmin Lee Hyunwoo Kim Hyunkoo Kang HyeSook Youn Sunmi Jo BuHyun Youn Hae Yu Kim 《International journal of molecular sciences》2021,22(10)
Although there are many patients with brain tumors worldwide, there are numerous difficulties in overcoming brain tumors. Among brain tumors, glioblastoma, with a 5-year survival rate of 5.1%, is the most malignant. In addition to surgical operations, chemotherapy and radiotherapy are generally performed, but the patients have very limited options. Temozolomide is the most commonly prescribed drug for patients with glioblastoma. However, it is difficult to completely remove the tumor with this drug alone. Therefore, it is necessary to discuss the potential of anticancer drugs, other than temozolomide, against glioblastomas. Since the discovery of cisplatin, platinum-based drugs have become one of the leading chemotherapeutic drugs. Although many studies have reported the efficacy of platinum-based anticancer drugs against various carcinomas, studies on their effectiveness against brain tumors are insufficient. In this review, we elucidated the anticancer effects and advantages of platinum-based drugs used in brain tumors. In addition, the cases and limitations of the clinical application of platinum-based drugs are summarized. As a solution to overcome these obstacles, we emphasized the potential of a novel approach to increase the effectiveness of platinum-based drugs. 相似文献
26.
Pil-Ryung Cha Ho-Seok Nam Dae-Yeong Jeon Jong-Kyu Yoon 《Metals and Materials International》2002,8(1):119-127
This study presents a simple and robust algorithm for the optimal design of the system with coupled complex transport phenomena:
the transport phenomena comprise fluid flow, heat and mass transfer. The (1+1)-Evolution Strategy method is adopted as the optimization method. In order to analyze the transport phenomena in the complex geometry generated
during the optimization procedure, thefinite volume method with a boundary fitted curvilinear coordinate system is used. To confirm the validity of the present method, the optimal
design for the inner shape of the simplified two-dimensionalSubmerged Entry Nozzle in the continuous slab caster is conducted. It is shown that the resulting design of the nozzle is consistent with the purpose
and constraints of the design. 相似文献
27.
In recent years, numerous analytical and experimental researches have been performed on the prediction of thermal stresses in mass concrete structures. However, due to the difficulty of the problem, limitations still exist for both analytical and experimental methods of measuring thermal stresses in mass concrete. In this research, a new experimental device measuring thermal stresses directly in a laboratory setting is developed. The equipment is located in a temperature chamber that follows the temperature history, which has been previously obtained from temperature distribution analyses. Thermal forces are measured continuously by two load cells in the device. The results show that the thermal stresses estimated by the newly developed device agree well with general stress variations in actual structures. 相似文献
28.
The effect of adsorbed polymer on the stability of alumina suspension was investigated. Poly(ethylene oxide) (PEO), poly(acrylic
acid) (PAA) and similar kinds of polymer salts were used as a dispersant. The amount of polymer adsorbed on alumina surface
and the suspension stability was measured. The pH, molecular weight, and concentration were considered as experimental parameters.
PEO shows low affinity on the alumina surface while PAA has high affinity. In the case of PAA adsorption, the surface charge
change by polymer adsorption influences suspension stability strongly, but not in the case of PEO adsorption. In simultaneous
adsorption of PEO and PAA, the PAA concentration was fixed and PEO concentration was varied. The stability of suspension increased
with increasing PEO concentration, and this is partly due to the steric stabilization by adsorption of PAA-PEO complex or
adsorption of PEO through pre-adsorbed PAA and the depletion effect of non-adsorbed polymer. Suspension adsorbing sodium salts
of PAA and poly(methacrylic acid) (PMA) each showed similar stability. But, when the PEO and these kinds of salts were added
together to the suspension, the one with PAA sodium salt could keep a higher stability even with lower molecular weights of
PEO compared with suspension with PMA sodium salt. 相似文献
29.
A new method of preparation of living cationic polymer of isobutyl vinyl ether via photoinduced polymerization in the presence of diphenyliodonium iodide (DPII, initiator) and zinc iodide in a mixed solvent of toluene/diethyl ether, which was irradiated at ?78°C for short period, was completed within 15 min. The reaction was allowed for further reaction in the dark until monomer was fully consumed. It was found that increase in the conversion of monomer to polymer during the irradiation is very limited. Confirmation of the linear dependence of number‐average molar mass of resulting polymer on % conversion together with the fact that polymerization proceeds until monomer consumption, and controllability of number‐average molar mass of resulting polymer, depending on the molar ratio of monomer and initiator, strongly suggests the living nature of this polymerization, unless reaction temperature becomes higher than 0°C, i.e., the absence of chain breaking process. The narrow molar mass distribution, whose polydispersity index values are less than 1.2, reveals that the rate of initiation where irradiation is usually completed within 15 min is much faster than that of propagation in cationic nature in this system. Effect of some major factors, such as solvent polarity and temperature, on the living nature of the polymerization was also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3581–3586, 2006 相似文献
30.
Hyun Jin Chung Suk Jin Chung Min Ku Jeon Seong Ihl Woo 《Korean Journal of Chemical Engineering》2006,23(2):329-332
The ((Bi3.5La0.5)Ti3O12(BLT) thin-films used in this study were fabricated on a Pt(111)/SiO2/Si(100) substrate by a Liquid Source Misted Chemical Deposition (LSMCD) technique. X-ray diffraction patterns showed that
the BLT films were crystallized and no other phases were observed when annealed above 650 ‡C. Grain size and remnant polarizations
increased with increase in the annealing temperature, while leakage current densities decreased. The remnant polarizations
(Pr) increased from 2.0 to 4.8 and 19.0 μC/cm2 with increase in the annealing temperature from 650 to 700 and 750 ‡C, respectively.
The BLT films annealed at 700 ‡C in O2 showed a good fatigue resistance of reduced polarization by 10% after 109 switching cycles when 9 V of bipolar voltage was applied at a frequency of 40 kHz. 相似文献